Bottle stopper



FIG. 1 is a perspective view of a bottle stopper showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof. The broken lines in FIG. 7 are included for the purpose of illustrating a portion of the bottom that forms no part of the claimed design. 

CLAIM The ornamental design for a bottle stopper, as shown. 